The present invention relates to a method of manufacturing a semiconductor device such as particularly dynamic random access memory (DRAM), particularly a semiconductor device having a capacitor with a fin type electrode.
A DRAM has been making a remarkable progress in its integration level. In recent years, 64 megabit DRAM has been already of practical use. In addition to remarkable progress of fine process technology, improvement of memory cell, structure also made a great contribution to the higher integration. Requirements for the higher integration of a DRAM brought about a semiconductor elements with a finer dimension. However, it caused a new problem; shortage (decrease in) of capacitor capacity. In order to recover the shortage of the capacitor capacity, polysilicon storing electric charge is usually formed being put on another to make multi-layer. One method is to form a so-called "fin structure", where a storage electrode is provided with a horizontal groove.
However, a problem about the prior art is that the manufacturing method of the fin type electrode of a capacitor element needs lots of time and manpower because of its complicated process. Another problem about the prior art is that shrinkage of a semiconductor element is difficult due to element's size limited by a marginal opening dimension of the contact because pattern dimension of the first polysilicon layer must be smaller than contact dimension of the intermediate film.